Commit 64e2a42b authored by Helge Deller's avatar Helge Deller
Browse files

parisc: Add ARCH_TRACEHOOK and regset support 



By adding TRACEHOOK support we now get a clean user interface to access
registers via PTRACE_GETREGS, PTRACE_SETREGS, PTRACE_GETFPREGS and
PTRACE_SETFPREGS.

The user-visible regset struct user_regs_struct and user_fp_struct are
modelled similiar to x86 and can be accessed via PTRACE_GETREGSET.

Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent d2ad824f

arch/parisc/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ config PARISC 
	select HAVE_DEBUG_STACKOVERFLOW

	select HAVE_ARCH_AUDITSYSCALL

	select HAVE_ARCH_SECCOMP_FILTER

	select HAVE_ARCH_TRACEHOOK

	select ARCH_NO_COHERENT_DMA_MMAP

	select CPU_NO_EFFICIENT_FFS

arch/parisc/include/uapi/asm/ptrace.h

+48 −0
Original line number Diff line number Diff line
@@ -13,6 +13,11 @@ 
 * N.B. gdb/strace care about the size and offsets within this

 * structure. If you change things, you may break object compatibility

 * for those applications.

 *

 * Please do NOT use this structure for future programs, but use

 * user_regs_struct (see below) instead.

 *

 * It can be accessed through PTRACE_PEEKUSR/PTRACE_POKEUSR only.

 */



struct pt_regs {
@@ -33,6 +38,45 @@ struct pt_regs { 
	unsigned long ipsw;	/* CR22 */

};



/**

 * struct user_regs_struct - User general purpose registers

 *

 * This is the user-visible general purpose register state structure

 * which is used to define the elf_gregset_t.

 *

 * It can be accessed through PTRACE_GETREGSET with NT_PRSTATUS

 * and through PTRACE_GETREGS.

 */

struct user_regs_struct {

	unsigned long gr[32];	/* PSW is in gr[0] */

	unsigned long sr[8];

	unsigned long iaoq[2];

	unsigned long iasq[2];

	unsigned long sar;	/* CR11 */

	unsigned long iir;	/* CR19 */

	unsigned long isr;	/* CR20 */

	unsigned long ior;	/* CR21 */

	unsigned long ipsw;	/* CR22 */

	unsigned long cr0;

	unsigned long cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;

	unsigned long cr8, cr9, cr12, cr13, cr10, cr15;

	unsigned long _pad[80-64];	/* pad to ELF_NGREG (80) */

};



/**

 * struct user_fp_struct - User floating point registers

 *

 * This is the user-visible floating point register state structure.

 * It uses the same layout and size as elf_fpregset_t.

 *

 * It can be accessed through PTRACE_GETREGSET with NT_PRFPREG

 * and through PTRACE_GETFPREGS.

 */

struct user_fp_struct {

	__u64 fr[32];

};





/*

 * The numbers chosen here are somewhat arbitrary but absolutely MUST

 * not overlap with any of the number assigned in <linux/ptrace.h>.
@@ -43,5 +87,9 @@ struct pt_regs { 
 */

#define PTRACE_SINGLEBLOCK	12	/* resume execution until next branch */



#define PTRACE_GETREGS		18

#define PTRACE_SETREGS		19

#define PTRACE_GETFPREGS	14

#define PTRACE_SETFPREGS	15



#endif /* _UAPI_PARISC_PTRACE_H */

arch/parisc/kernel/ptrace.c

+354 −2
Original line number Diff line number Diff line
@@ -4,18 +4,20 @@ 
 * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.

 * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>

 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>

 * Copyright (C) 2008 Helge Deller <deller@gmx.de>

 * Copyright (C) 2008-2016 Helge Deller <deller@gmx.de>

 */



#include <linux/kernel.h>

#include <linux/sched.h>

#include <linux/mm.h>

#include <linux/smp.h>

#include <linux/elf.h>

#include <linux/errno.h>

#include <linux/ptrace.h>

#include <linux/tracehook.h>

#include <linux/user.h>

#include <linux/personality.h>

#include <linux/regset.h>

#include <linux/security.h>

#include <linux/seccomp.h>

#include <linux/compat.h>
@@ -33,6 +35,14 @@ 
#define CREATE_TRACE_POINTS

#include <trace/events/syscalls.h>



/*

 * These are our native regset flavors.

 */

enum parisc_regset {

	REGSET_GENERAL,

	REGSET_FP

};



/*

 * Called by kernel/ptrace.c when detaching..

 *
@@ -117,6 +127,7 @@ void user_enable_block_step(struct task_struct *task) 
long arch_ptrace(struct task_struct *child, long request,

		 unsigned long addr, unsigned long data)

{

	unsigned long __user *datap = (unsigned long __user *)data;

	unsigned long tmp;

	long ret = -EIO;
@@ -129,7 +140,7 @@ long arch_ptrace(struct task_struct *child, long request, 
		     addr >= sizeof(struct pt_regs))

			break;

		tmp = *(unsigned long *) ((char *) task_regs(child) + addr);

		ret = put_user(tmp, (unsigned long __user *) data);

		ret = put_user(tmp, datap);

		break;



	/* Write the word at location addr in the USER area.  This will need
@@ -168,6 +179,34 @@ long arch_ptrace(struct task_struct *child, long request, 
		}

		break;



	case PTRACE_GETREGS:	/* Get all gp regs from the child. */

		return copy_regset_to_user(child,

					   task_user_regset_view(current),

					   REGSET_GENERAL,

					   0, sizeof(struct user_regs_struct),

					   datap);



	case PTRACE_SETREGS:	/* Set all gp regs in the child. */

		return copy_regset_from_user(child,

					     task_user_regset_view(current),

					     REGSET_GENERAL,

					     0, sizeof(struct user_regs_struct),

					     datap);



	case PTRACE_GETFPREGS:	/* Get the child FPU state. */

		return copy_regset_to_user(child,

					   task_user_regset_view(current),

					   REGSET_FP,

					   0, sizeof(struct user_fp_struct),

					   datap);



	case PTRACE_SETFPREGS:	/* Set the child FPU state. */

		return copy_regset_from_user(child,

					     task_user_regset_view(current),

					     REGSET_FP,

					     0, sizeof(struct user_fp_struct),

					     datap);



	default:

		ret = ptrace_request(child, request, addr, data);

		break;
@@ -326,3 +365,316 @@ void do_syscall_trace_exit(struct pt_regs *regs) 
	if (stepping || test_thread_flag(TIF_SYSCALL_TRACE))

		tracehook_report_syscall_exit(regs, stepping);

}





/*

 * regset functions.

 */



static int fpr_get(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     void *kbuf, void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	__u64 *k = kbuf;

	__u64 __user *u = ubuf;

	__u64 reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NFPREG; --count)

			*k++ = regs->fr[pos++];

	else

		for (; count > 0 && pos < ELF_NFPREG; --count)

			if (__put_user(regs->fr[pos++], u++))

				return -EFAULT;



	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,

					ELF_NFPREG * sizeof(reg), -1);

}



static int fpr_set(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     const void *kbuf, const void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	const __u64 *k = kbuf;

	const __u64 __user *u = ubuf;

	__u64 reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NFPREG; --count)

			regs->fr[pos++] = *k++;

	else

		for (; count > 0 && pos < ELF_NFPREG; --count) {

			if (__get_user(reg, u++))

				return -EFAULT;

			regs->fr[pos++] = reg;

		}



	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,

					 ELF_NFPREG * sizeof(reg), -1);

}



#define RI(reg) (offsetof(struct user_regs_struct,reg) / sizeof(long))



static unsigned long get_reg(struct pt_regs *regs, int num)

{

	switch (num) {

	case RI(gr[0]) ... RI(gr[31]):	return regs->gr[num - RI(gr[0])];

	case RI(sr[0]) ... RI(sr[7]):	return regs->sr[num - RI(sr[0])];

	case RI(iasq[0]):		return regs->iasq[0];

	case RI(iasq[1]):		return regs->iasq[1];

	case RI(iaoq[0]):		return regs->iaoq[0];

	case RI(iaoq[1]):		return regs->iaoq[1];

	case RI(sar):			return regs->sar;

	case RI(iir):			return regs->iir;

	case RI(isr):			return regs->isr;

	case RI(ior):			return regs->ior;

	case RI(ipsw):			return regs->ipsw;

	case RI(cr27):			return regs->cr27;

	case RI(cr0):			return mfctl(0);

	case RI(cr24):			return mfctl(24);

	case RI(cr25):			return mfctl(25);

	case RI(cr26):			return mfctl(26);

	case RI(cr28):			return mfctl(28);

	case RI(cr29):			return mfctl(29);

	case RI(cr30):			return mfctl(30);

	case RI(cr31):			return mfctl(31);

	case RI(cr8):			return mfctl(8);

	case RI(cr9):			return mfctl(9);

	case RI(cr12):			return mfctl(12);

	case RI(cr13):			return mfctl(13);

	case RI(cr10):			return mfctl(10);

	case RI(cr15):			return mfctl(15);

	default:			return 0;

	}

}



static void set_reg(struct pt_regs *regs, int num, unsigned long val)

{

	switch (num) {

	case RI(gr[0]): /*

			 * PSW is in gr[0].

			 * Allow writing to Nullify, Divide-step-correction,

			 * and carry/borrow bits.

			 * BEWARE, if you set N, and then single step, it won't

			 * stop on the nullified instruction.

			 */

			val &= USER_PSW_BITS;

			regs->gr[0] &= ~USER_PSW_BITS;

			regs->gr[0] |= val;

			return;

	case RI(gr[1]) ... RI(gr[31]):

			regs->gr[num - RI(gr[0])] = val;

			return;

	case RI(iaoq[0]):

	case RI(iaoq[1]):

			regs->iaoq[num - RI(iaoq[0])] = val;

			return;

	case RI(sar):	regs->sar = val;

			return;

	default:	return;

#if 0

	/* do not allow to change any of the following registers (yet) */

	case RI(sr[0]) ... RI(sr[7]):	return regs->sr[num - RI(sr[0])];

	case RI(iasq[0]):		return regs->iasq[0];

	case RI(iasq[1]):		return regs->iasq[1];

	case RI(iir):			return regs->iir;

	case RI(isr):			return regs->isr;

	case RI(ior):			return regs->ior;

	case RI(ipsw):			return regs->ipsw;

	case RI(cr27):			return regs->cr27;

        case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;

        case cr8, cr9, cr12, cr13, cr10, cr15;

#endif

	}

}



static int gpr_get(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     void *kbuf, void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	unsigned long *k = kbuf;

	unsigned long __user *u = ubuf;

	unsigned long reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NGREG; --count)

			*k++ = get_reg(regs, pos++);

	else

		for (; count > 0 && pos < ELF_NGREG; --count)

			if (__put_user(get_reg(regs, pos++), u++))

				return -EFAULT;

	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,

					ELF_NGREG * sizeof(reg), -1);

}



static int gpr_set(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     const void *kbuf, const void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	const unsigned long *k = kbuf;

	const unsigned long __user *u = ubuf;

	unsigned long reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NGREG; --count)

			set_reg(regs, pos++, *k++);

	else

		for (; count > 0 && pos < ELF_NGREG; --count) {

			if (__get_user(reg, u++))

				return -EFAULT;

			set_reg(regs, pos++, reg);

		}



	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,

					 ELF_NGREG * sizeof(reg), -1);

}



static const struct user_regset native_regsets[] = {

	[REGSET_GENERAL] = {

		.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,

		.size = sizeof(long), .align = sizeof(long),

		.get = gpr_get, .set = gpr_set

	},

	[REGSET_FP] = {

		.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,

		.size = sizeof(__u64), .align = sizeof(__u64),

		.get = fpr_get, .set = fpr_set

	}

};



static const struct user_regset_view user_parisc_native_view = {

	.name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX,

	.regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)

};



#ifdef CONFIG_64BIT

#include <linux/compat.h>



static int gpr32_get(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     void *kbuf, void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	compat_ulong_t *k = kbuf;

	compat_ulong_t __user *u = ubuf;

	compat_ulong_t reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NGREG; --count)

			*k++ = get_reg(regs, pos++);

	else

		for (; count > 0 && pos < ELF_NGREG; --count)

			if (__put_user((compat_ulong_t) get_reg(regs, pos++), u++))

				return -EFAULT;



	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,

					ELF_NGREG * sizeof(reg), -1);

}



static int gpr32_set(struct task_struct *target,

		     const struct user_regset *regset,

		     unsigned int pos, unsigned int count,

		     const void *kbuf, const void __user *ubuf)

{

	struct pt_regs *regs = task_regs(target);

	const compat_ulong_t *k = kbuf;

	const compat_ulong_t __user *u = ubuf;

	compat_ulong_t reg;



	pos /= sizeof(reg);

	count /= sizeof(reg);



	if (kbuf)

		for (; count > 0 && pos < ELF_NGREG; --count)

			set_reg(regs, pos++, *k++);

	else

		for (; count > 0 && pos < ELF_NGREG; --count) {

			if (__get_user(reg, u++))

				return -EFAULT;

			set_reg(regs, pos++, reg);

		}



	kbuf = k;

	ubuf = u;

	pos *= sizeof(reg);

	count *= sizeof(reg);

	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,

					 ELF_NGREG * sizeof(reg), -1);

}



/*

 * These are the regset flavors matching the 32bit native set.

 */

static const struct user_regset compat_regsets[] = {

	[REGSET_GENERAL] = {

		.core_note_type = NT_PRSTATUS, .n = ELF_NGREG,

		.size = sizeof(compat_long_t), .align = sizeof(compat_long_t),

		.get = gpr32_get, .set = gpr32_set

	},

	[REGSET_FP] = {

		.core_note_type = NT_PRFPREG, .n = ELF_NFPREG,

		.size = sizeof(__u64), .align = sizeof(__u64),

		.get = fpr_get, .set = fpr_set

	}

};



static const struct user_regset_view user_parisc_compat_view = {

	.name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX,

	.regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)

};

#endif	/* CONFIG_64BIT */



const struct user_regset_view *task_user_regset_view(struct task_struct *task)

{

	BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG);

	BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG);

#ifdef CONFIG_64BIT

	if (is_compat_task())

		return &user_parisc_compat_view;

#endif

	return &user_parisc_native_view;

}

tools/testing/selftests/seccomp/seccomp_bpf.c

+7 −1
Original line number Diff line number Diff line
@@ -1234,6 +1234,10 @@ TEST_F(TRACE_poke, getpid_runs_normally) 
# define ARCH_REGS	struct user_pt_regs

# define SYSCALL_NUM	regs[8]

# define SYSCALL_RET	regs[0]

#elif defined(__hppa__)

# define ARCH_REGS	struct user_regs_struct

# define SYSCALL_NUM	gr[20]

# define SYSCALL_RET	gr[28]

#elif defined(__powerpc__)

# define ARCH_REGS	struct pt_regs

# define SYSCALL_NUM	gpr[0]
@@ -1303,7 +1307,7 @@ void change_syscall(struct __test_metadata *_metadata, 
	EXPECT_EQ(0, ret);



#if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \

    defined(__s390__)

    defined(__s390__) || defined(__hppa__)

	{

		regs.SYSCALL_NUM = syscall;

	}
@@ -1505,6 +1509,8 @@ TEST_F(TRACE_syscall, syscall_dropped) 
#  define __NR_seccomp 383

# elif defined(__aarch64__)

#  define __NR_seccomp 277

# elif defined(__hppa__)

#  define __NR_seccomp 338

# elif defined(__powerpc__)

#  define __NR_seccomp 358

# elif defined(__s390__)

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